3

Multimedia ICs

BA7725S / BA7725FS

Pin name

Function

BA7725S

BA7725FS

1

1

LINE OUT

Line output

2

2

LINE IN

Line input

3—

—

—

N.C.

4

3

ECHO LEV CTRL

Microphone turns off when voltage drops below 1V.

Set echo signal damping ratio between 2-9V (Vcc = 9.0V).

5

4

GND

Ground

6

5

LOOP GAIN CTRL

Setting the loop damping ratio. Set between

2-9V (Vcc = 9.0V).

7

6

EXP DET

Expand detection

8

7

EXP DET CT

9

8

EXP BF OUT

LPF BF output (expansion)

10

9

EXP BF IN

LPF BF input (expansion)

11

10

DLY BF OUT

Echo signal input BF output

12

11

DLY BF IN

Echo signal input BF input

13

12

CMP BF OUT

LPF BF output (compression)

14

13

CMP BF IN

LPF BF input (compression)

15

14

CMP OUT

Compression output

16

15

CMP DET CT

17

16

CMP DET

Compression detection

18

17

RIPPLE FITER

Attached ripple rejection capacitor

19

18

20

—

N.C.

21

19

MIC AMP OUT

Microphone amplifier output

22

20

MIC AMP IN

Microphone amplifier input

Setting expand attack / recovery time

Attack (R) = 5.6k

Ω, recovery (R) = 85.6kΩ

Setting the compression attack / recovery time

Attack (R) = 5.6k

Ω, recovery (R) = 85.6kΩ

Pin No.